Small cell carcinoma

Topic Completed: 1 August 2011

Minor changes: 25 February 2019

Copyright: 2002-2017, PathologyOutlines.com, Inc.

PubMed search: small cell carcinoma uterus

Mohamed Mokhtar Desouki, M.D., Ph.D.
Page views in 2019: 1,127
Page views in 2020 to date: 818
Cite this page: Desouki M. Small cell carcinoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/uterussmallcell.html. Accessed August 6th, 2020.
Definition / general
  • Aggressive carcinoma of definite endometrial origin resembling small cell carcinoma of the lung and other organs
  • Note: 25% - 50% of typical endometrial adenocarcinomas contain some endocrine cells
  • Also called oat cell carcinoma of endometrium, neuroendocrine small cell carcinoma of endometrium
  • Uncommon, < 1% of endometrial carcinomas, ~60 cases reported in English literature
  • Mean age 60 years, range 23 - 78 years
  • Originates at body or isthmus with no cervical involvement
  • Nonprimary cases may originate in cervix and extend to uterine corpus
  • Unknown
  • Heterotopic nuclear localization of beta-catenin may play a role in invasion and be associated with aggressive behavior
  • Associated with endometrioid adenocarcinoma, adenosquamous carcinomas, mixed Müllerian tumors and endometrial stromal sarcomas in some cases, but pure tumors also reported
Clinical features
  • Abnormal vaginal bleeding or pain related to metastatic tumor
  • No reported cases in nulliparous patients
Case reports
Prognostic factors
  • Stage I tumors have 5 year survival of 60%
  • Total abdominal hysterectomy, bilateral salpingo-oophorectomy and pelvic and paraaortic lymph node dissection, followed by radiation therapy and chemotherapy (Semin Oncol 2007;34:57)
Gross description
  • Bulky, polypoid, ill defined with invasion of myometrium
Microscopic (histologic) description
  • Resembles small cell carcinoma at different sites
  • Cells are small to intermediate size forming sheets, cords and nests, as well as single cells with scanty cytoplasm, hyperchromatic nuclei and high mitotic rate (Am J Surg Pathol 1994;18:364)
  • Zonal necrosis and vascular invasion are common
  • Complex atypical endometrial hyperplasia may be present adjacent to the tumor
Microscopic (histologic) images

Images hosted on PathOut server:

Resembles small cell carcinoma of lung

Images hosted on other servers:

Resembles small cell carcinoma of lung

Cytology description
  • Cytologically similar to counterparts in lung and other sites
  • Small tumor cells arranged as single cells or in groups and cords with barely visible cytoplasm, darkly staining nuclei with finely stippled chromatin with characteristic molding and inconspicuous nucleoli (TEXTActa Cytol 1998;42:978)
  • Differential diagnosis includes adenocarcinoma with neuroendocrine features, small cell nonkeratinizing squamous cell carcinoma, endometrial stromal sarcoma, rhabdomyosarcoma, primitive neuroectodermal tumor, non Hodgkin lymphoma, metastatic breast carcinoma
Cytology images

Images hosted on other servers:

Pleural fluid

Electron microscopy description
  • Cytoplasmic dense core secretory granules and indistinct cell junctions (J Obstet Gynaecol Res 1997;23:9)
  • Intense nuclear beta-catenin accumulation and cyclin D1 immunoreactivity restricted to carcinoma cells invading lymphatic vessels, although no mutation in exon 3 of the beta-catenin gene or exon 15 of the APC gene
Differential diagnosis
Back to top